Nothing in this particular blog entry is theoretically new. In a discussion of scientists' roles in academic controversies, fellow Psychology Today blogger Scott Lilienfeld proposes that psychologists should more actively correct logical errors associated with their research, and I agree. Unfortunately, in the study of the evolution of behavior, the same exact logical errors have persisted for decades. In my first blog entries, I hope to bring some of these errors to light in this casual and public domain.
Earlier this year, Sharon Begley published a criticism of evolutionary psychological research in Newsweek, which contained several factual and logical errors. Criticisms of using evolution to understand behavior often include factual or logical errors; for example, critics often attack evolutionary logic as both unfalsifiable and incorrect in the same essay. Fellow Psychology Today blogger Douglas Kenrick wrote one of my favorite reviews of criticisms of evolutionary logic, and certainly the best titled one: "Evolutionary Theory versus the Confederacy of Dunces." A particular misunderstanding of evolutionary theory underlies many of these criticisms, specifically the notion that evolutionary theorists ignore environmental influences on behavior.
The reader has doubtlessly heard of evolutionary hypotheses as "biological" explanations for behavior and has probably heard these contrasted with "social" or "environmental" hypotheses. While I think that this contrast makes intuitive sense to lots of us, the problem is that it is nonsensical. Any behavior requires a specific collection of genes and environments to exist. Crawdads don't learn to speak English, whether or not they are raised in an environment in which they hear lots of English throughout their lives. Therefore, there must be some genes essential for learning English. However, as humans raised in environments in which they are never exposed to English never learn to speak English, it must be the case that environmental influences also contribute to the ability to speak English. Again, only a specific combination of genes and environments will contribute to the expression of any trait or behavior. This seems obvious, right?
Well, it doesn't seem to be obvious to critics of the application of evolutionary theory to understanding behavior. For example, Begley cites the fact that stepfathers do not always kill their stepchildren as evidence that "there is no universal human nature as evo psych defines it." Of course, this is absurd. First of all, no evolutionary hypothesis ever predicted that all stepfathers would always kill their stepchildren. In fact, Begley's fallacy, assuming that evolutionary theory does not allow for behavioral flexibility, is evidenced by her very choice of words. The term "stepfather" carries both genetic (is male) and environmental (is in a relationship with a woman who already has children) meanings. So even assuming that Begley was accurately representing an evolutionary hypothesis, she would still be granting that evolutionary psychology allows for environmental influences on behavior. And in reality, evolutionary researchers have suggested that stepfather abuse is much more influenced by environmental factors than she has claimed they do.
As I hope I have clearly demonstrated, the question of whether hypotheses of behavior stemming from evolutionary hypotheses is not a very interesting one. More interesting are the issues of how selection has prepared individuals to behave differently in different environments and how individuals act in environments in which their genes have not yet undergone extensive selection.
